I have in our facility Wartsila SW 18 V 38 series engines each rated at 11.3 MW the engine is V-Line with 09 pistons on each bank there are two turbochargers ABB VTR 454 series.The engines have covered 60,000 hours and 10 years of operation.

The frequency of water leakage into the turbo side gas inlet and central casing has increased over the last 06 months we usually replace the casing with a repaired one but the leakage keeps on coming after a few months what could be the reason.

The engines run on heavy fuel and the casing are cooled by HT CW of the engine.

Let's keep this simple:
Does this happen to just the engines with rebuilt trubos, and did it only begin when you started using rebuilt turbos?
......assuming your turbos are water cooled... 'else how could water get to the air side at the turbo... assuming you are accurate and water really is getting to the air side as you have described.

...if yes.... the seals between the water coolant and air side of the rebuilt turbos is not installed correctly or is of improper material or similar problem with the rebuild.

...if no.... Do you have water in the oil, too?

...if yes... Check the inter coolers if you have them. They can develop leaks between the water and oil side. This means you have other serious problems which eventually effect the turbos.

...if no... Do you have high pressure in the water coolant side?

...if yes... You will be having coolant heat problems and exhaust excaping from the heat exchangers in the form of burping. This can cause failure of the seals between the water side and air side of the turbos. To my knowledge, coolant water should NEVER exceed 20 PSI. This would most likely indicate that you have cracked engines blocks.

..else.. there are many possible reasons this could happen that would take a certified mechainc to figure out by being on site to witness the happening. The above are just a few of the most likely sceneros.

With a most sincere honesty, ... I would be doing you wrong if I did not express the following, please receive it as a heart felt desire to help:
... after watching your posts for several months it seems in my experienced opinion, and friendly desire to help, that you should hire a well qualified and CERTIFIED (certified by a seriously accredited program) engine mechanic to over see all your maintenance, general engine operations, and repairs, ...FULL TIME ON STAFF. It too seems to me that this person would assist in preventing numerous enough mistakes being made to far exceed the price of their wages. Your questions reapeatedly express a sincere cry for help and a desire to find answers. This person could provide the required stronger talents, skills, and aptitude in mechancial areas. The questions you sincerely ask, by themselves, are evidence enough that the necessary skills and knowledge required to maintain these power plants effeciently are apparently not available to your staff. A properly certified person would know the answers to these questions and have the diagnostic skills to find proper solutions. Your team would be much happier and complete with such an added member. Without making such a change in this direction you will surely continue to have serious problems and perhaps even eventually destroy the engines. I would imagine your repair hours and costs would go down, even with the added staff member.

..good luck...

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